package com.chengqs.netty.c2;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.string.StringDecoder;

public class HelloServer {
    public static void main(String[] args) {
        // 1. 启动器，负责组装 netty 组件，启动服务器
        new ServerBootstrap()
                // 2. BossEventLoopGroup，处理连接请求，真正处理请求的是 WorkerEventLoopGroup(Selector, thread), group 组
                .group(new NioEventLoopGroup())
                // 3. 选择服务器的 ServerSocketChannel 实现
                .channel(NioServerSocketChannel.class) // |OIO BIO
                // 4. boss 负责处理连接 worker(child) 负责处理读写，决定了 worker(child) 可以处理哪些操作(I/O, timer)
                .childHandler(
                        // 5. 代表和客户端进行数据读写的通道 Initializer 初始化，负责添加别的 handler
                        new ChannelInitializer<NioSocketChannel>() {
                            @Override
                            protected void initChannel(NioSocketChannel nioSocketChannel) throws Exception {
                                // 6. 添加具体 handler
                                nioSocketChannel.pipeline().addLast(new StringDecoder()); // 将 ByteBuf 转换为字符串
                                nioSocketChannel.pipeline().addLast(new ChannelInboundHandlerAdapter() { // 自定义 handler
                                    @Override
                                    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
                                        System.out.println(msg);
                                        ctx.fireChannelRead(msg); // 必须传递给下一个handler
                                        // super.channelRead(ctx, msg);
                                    }
                                });
                                nioSocketChannel.pipeline().addLast(new ChannelInboundHandlerAdapter() {
                                    @Override
                                    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
                                        System.out.println("2: " + msg);
                                    }
                                });
                            }
                        })
                // 7. 绑定监听端口
                .bind(8080);
    }
}
